/*
* Copyright (c) 2006-2007 Erin Catto http:
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked, and must not be
* misrepresented the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
// var b2PulleyJoint = Class.create();
// Object.extend(b2PulleyJoint.prototype, b2Joint.prototype);
// Object.extend(b2PulleyJoint.prototype,
import b2Vec2 from '../../common/math/b2Vec2';
import b2Math from '../../common/math/b2Math';
import b2Settings from '../../common/b2Settings';
import b2Joint from './b2Joint';
import b2JointNode from './b2JointNode';
export default class b2PulleyJoint extends b2Joint {
    //--------------- Internals Below -------------------
    constructor(def) {
        super(def);
        this.m_ground = null;
        this.m_groundAnchor1 = null;
        this.m_groundAnchor2 = null;
        this.m_localAnchor1 = null;
        this.m_localAnchor2 = null;
        this.m_u1 = null;
        this.m_u2 = null;
        this.m_constant = 0;
        this.m_ratio = 0;
        this.m_maxLength1 = 0;
        this.m_maxLength2 = 0;
        // Effective masses
        this.m_pulleyMass = 0;
        this.m_limitMass1 = 0;
        this.m_limitMass2 = 0;
        // Impulses for accumulation/warm starting.
        this.m_pulleyImpulse = 0;
        this.m_limitImpulse1 = 0;
        this.m_limitImpulse2 = 0;
        // Position impulses for accumulation.
        this.m_limitPositionImpulse1 = 0;
        this.m_limitPositionImpulse2 = 0;
        this.m_limitState1 = 0;
        this.m_limitState2 = 0;
        // The constructor for b2Joint
        // initialize instance variables for references
        this.m_node1 = new b2JointNode();
        this.m_node2 = new b2JointNode();
        //
        this.m_type = def.type;
        this.m_prev = null;
        this.m_next = null;
        this.m_body1 = def.body1;
        this.m_body2 = def.body2;
        this.m_collideConnected = def.collideConnected;
        this.m_islandFlag = false;
        this.m_userData = def.userData;
        //
        // initialize instance variables for references
        this.m_groundAnchor1 = new b2Vec2();
        this.m_groundAnchor2 = new b2Vec2();
        this.m_localAnchor1 = new b2Vec2();
        this.m_localAnchor2 = new b2Vec2();
        this.m_u1 = new b2Vec2();
        this.m_u2 = new b2Vec2();
        //
        // parent
        //super(def);
        var tMat;
        var tX;
        var tY;
        this.m_ground = this.m_body1.m_world.m_groundBody;
        //this.m_groundAnchor1 = def.groundPoint1 - this.m_ground.m_position;
        this.m_groundAnchor1.x = def.groundPoint1.x - this.m_ground.m_position.x;
        this.m_groundAnchor1.y = def.groundPoint1.y - this.m_ground.m_position.y;
        //this.m_groundAnchor2 = def.groundPoint2 - this.m_ground.m_position;
        this.m_groundAnchor2.x = def.groundPoint2.x - this.m_ground.m_position.x;
        this.m_groundAnchor2.y = def.groundPoint2.y - this.m_ground.m_position.y;
        //this.m_localAnchor1 = b2MulT(this.m_body1.m_R, def.anchorPoint1 - this.m_body1.m_position);
        tMat = this.m_body1.m_R;
        tX = def.anchorPoint1.x - this.m_body1.m_position.x;
        tY = def.anchorPoint1.y - this.m_body1.m_position.y;
        this.m_localAnchor1.x = tX * tMat.col1.x + tY * tMat.col1.y;
        this.m_localAnchor1.y = tX * tMat.col2.x + tY * tMat.col2.y;
        //this.m_localAnchor2 = b2MulT(this.m_body2.m_R, def.anchorPoint2 - this.m_body2.m_position);
        tMat = this.m_body2.m_R;
        tX = def.anchorPoint2.x - this.m_body2.m_position.x;
        tY = def.anchorPoint2.y - this.m_body2.m_position.y;
        this.m_localAnchor2.x = tX * tMat.col1.x + tY * tMat.col1.y;
        this.m_localAnchor2.y = tX * tMat.col2.x + tY * tMat.col2.y;
        this.m_ratio = def.ratio;
        //var d1 = def.groundPoint1 - def.anchorPoint1;
        tX = def.groundPoint1.x - def.anchorPoint1.x;
        tY = def.groundPoint1.y - def.anchorPoint1.y;
        var d1Len = Math.sqrt(tX * tX + tY * tY);
        //var d2 = def.groundPoint2 - def.anchorPoint2;
        tX = def.groundPoint2.x - def.anchorPoint2.x;
        tY = def.groundPoint2.y - def.anchorPoint2.y;
        var d2Len = Math.sqrt(tX * tX + tY * tY);
        var length1 = b2Math.b2Max(0.5 * b2PulleyJoint.b2_minPulleyLength, d1Len);
        var length2 = b2Math.b2Max(0.5 * b2PulleyJoint.b2_minPulleyLength, d2Len);
        this.m_constant = length1 + this.m_ratio * length2;
        this.m_maxLength1 = b2Math.b2Clamp(def.maxLength1, length1, this.m_constant - this.m_ratio * b2PulleyJoint.b2_minPulleyLength);
        this.m_maxLength2 = b2Math.b2Clamp(def.maxLength2, length2, (this.m_constant - b2PulleyJoint.b2_minPulleyLength) / this.m_ratio);
        this.m_pulleyImpulse = 0.0;
        this.m_limitImpulse1 = 0.0;
        this.m_limitImpulse2 = 0.0;
    }
    static Create(def) {
        return new b2PulleyJoint(def);
    }
    GetAnchor1() {
        //return this.m_body1->m_position + b2Mul(this.m_body1->m_R, this.m_localAnchor1);
        var tMat = this.m_body1.m_R;
        return new b2Vec2(this.m_body1.m_position.x + (tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y), this.m_body1.m_position.y + (tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y));
    }
    GetAnchor2() {
        //return this.m_body2->m_position + b2Mul(this.m_body2->m_R, this.m_localAnchor2);
        var tMat = this.m_body2.m_R;
        return new b2Vec2(this.m_body2.m_position.x + (tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y), this.m_body2.m_position.y + (tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y));
    }
    GetGroundPoint1() {
        //return this.m_ground->m_position + this.m_groundAnchor1;
        return new b2Vec2(this.m_ground.m_position.x + this.m_groundAnchor1.x, this.m_ground.m_position.y + this.m_groundAnchor1.y);
    }
    GetGroundPoint2() {
        return new b2Vec2(this.m_ground.m_position.x + this.m_groundAnchor2.x, this.m_ground.m_position.y + this.m_groundAnchor2.y);
    }
    GetReactionForce(invTimeStep) {
        //b2Vec2 F(0.0f, 0.0f);
        return new b2Vec2();
    }
    GetReactionTorque(invTimeStep) {
        return 0.0;
    }
    GetLength1() {
        var tMat;
        //b2Vec2 p = this.m_body1->m_position + b2Mul(this.m_body1->m_R, this.m_localAnchor1);
        tMat = this.m_body1.m_R;
        var pX = this.m_body1.m_position.x + (tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y);
        var pY = this.m_body1.m_position.y + (tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y);
        //b2Vec2 s = this.m_ground->m_position + this.m_groundAnchor1;
        //b2Vec2 d = p - s;
        var dX = pX - (this.m_ground.m_position.x + this.m_groundAnchor1.x);
        var dY = pY - (this.m_ground.m_position.y + this.m_groundAnchor1.y);
        return Math.sqrt(dX * dX + dY * dY);
    }
    GetLength2() {
        var tMat;
        //b2Vec2 p = this.m_body2->m_position + b2Mul(this.m_body2->m_R, this.m_localAnchor2);
        tMat = this.m_body2.m_R;
        var pX = this.m_body2.m_position.x + (tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y);
        var pY = this.m_body2.m_position.y + (tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y);
        //b2Vec2 s = this.m_ground->m_position + this.m_groundAnchor2;
        //b2Vec2 d = p - s;
        var dX = pX - (this.m_ground.m_position.x + this.m_groundAnchor2.x);
        var dY = pY - (this.m_ground.m_position.y + this.m_groundAnchor2.y);
        return Math.sqrt(dX * dX + dY * dY);
    }
    GetRatio() {
        return this.m_ratio;
    }
    PrepareVelocitySolver() {
        var b1 = this.m_body1;
        var b2 = this.m_body2;
        var tMat;
        //b2Vec2 r1 = b2Mul(b1->m_R, this.m_localAnchor1);
        tMat = b1.m_R;
        var r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
        var r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
        //b2Vec2 r2 = b2Mul(b2->m_R, this.m_localAnchor2);
        tMat = b2.m_R;
        var r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
        var r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
        //b2Vec2 p1 = b1->m_position + r1;
        var p1X = b1.m_position.x + r1X;
        var p1Y = b1.m_position.y + r1Y;
        //b2Vec2 p2 = b2->m_position + r2;
        var p2X = b2.m_position.x + r2X;
        var p2Y = b2.m_position.y + r2Y;
        //b2Vec2 s1 = this.m_ground->m_position + this.m_groundAnchor1;
        var s1X = this.m_ground.m_position.x + this.m_groundAnchor1.x;
        var s1Y = this.m_ground.m_position.y + this.m_groundAnchor1.y;
        //b2Vec2 s2 = this.m_ground->m_position + this.m_groundAnchor2;
        var s2X = this.m_ground.m_position.x + this.m_groundAnchor2.x;
        var s2Y = this.m_ground.m_position.y + this.m_groundAnchor2.y;
        // Get the pulley axes.
        //this.m_u1 = p1 - s1;
        this.m_u1.Set(p1X - s1X, p1Y - s1Y);
        //this.m_u2 = p2 - s2;
        this.m_u2.Set(p2X - s2X, p2Y - s2Y);
        var length1 = this.m_u1.Length();
        var length2 = this.m_u2.Length();
        if (length1 > b2Settings.b2_linearSlop) {
            //this.m_u1 *= 1.0f / length1;
            this.m_u1.Multiply(1.0 / length1);
        }
        else {
            this.m_u1.SetZero();
        }
        if (length2 > b2Settings.b2_linearSlop) {
            //this.m_u2 *= 1.0f / length2;
            this.m_u2.Multiply(1.0 / length2);
        }
        else {
            this.m_u2.SetZero();
        }
        if (length1 < this.m_maxLength1) {
            this.m_limitState1 = b2Joint.e_inactiveLimit;
            this.m_limitImpulse1 = 0.0;
        }
        else {
            this.m_limitState1 = b2Joint.e_atUpperLimit;
            this.m_limitPositionImpulse1 = 0.0;
        }
        if (length2 < this.m_maxLength2) {
            this.m_limitState2 = b2Joint.e_inactiveLimit;
            this.m_limitImpulse2 = 0.0;
        }
        else {
            this.m_limitState2 = b2Joint.e_atUpperLimit;
            this.m_limitPositionImpulse2 = 0.0;
        }
        // Compute effective mass.
        //var cr1u1 = b2Cross(r1, this.m_u1);
        var cr1u1 = r1X * this.m_u1.y - r1Y * this.m_u1.x;
        //var cr2u2 = b2Cross(r2, this.m_u2);
        var cr2u2 = r2X * this.m_u2.y - r2Y * this.m_u2.x;
        this.m_limitMass1 = b1.m_invMass + b1.m_invI * cr1u1 * cr1u1;
        this.m_limitMass2 = b2.m_invMass + b2.m_invI * cr2u2 * cr2u2;
        this.m_pulleyMass = this.m_limitMass1 + this.m_ratio * this.m_ratio * this.m_limitMass2;
        //b2Settings.b2Assert(this.m_limitMass1 > Number.MIN_VALUE);
        //b2Settings.b2Assert(this.m_limitMass2 > Number.MIN_VALUE);
        //b2Settings.b2Assert(this.m_pulleyMass > Number.MIN_VALUE);
        this.m_limitMass1 = 1.0 / this.m_limitMass1;
        this.m_limitMass2 = 1.0 / this.m_limitMass2;
        this.m_pulleyMass = 1.0 / this.m_pulleyMass;
        // Warm starting.
        //b2Vec2 P1 = (-this.m_pulleyImpulse - this.m_limitImpulse1) * this.m_u1;
        var P1X = (-this.m_pulleyImpulse - this.m_limitImpulse1) * this.m_u1.x;
        var P1Y = (-this.m_pulleyImpulse - this.m_limitImpulse1) * this.m_u1.y;
        //b2Vec2 P2 = (-this.m_ratio * this.m_pulleyImpulse - this.m_limitImpulse2) * this.m_u2;
        var P2X = (-this.m_ratio * this.m_pulleyImpulse - this.m_limitImpulse2) * this.m_u2.x;
        var P2Y = (-this.m_ratio * this.m_pulleyImpulse - this.m_limitImpulse2) * this.m_u2.y;
        //b1.m_linearVelocity += b1.m_invMass * P1;
        b1.m_linearVelocity.x += b1.m_invMass * P1X;
        b1.m_linearVelocity.y += b1.m_invMass * P1Y;
        //b1.m_angularVelocity += b1.m_invI * b2Cross(r1, P1);
        b1.m_angularVelocity += b1.m_invI * (r1X * P1Y - r1Y * P1X);
        //b2.m_linearVelocity += b2.m_invMass * P2;
        b2.m_linearVelocity.x += b2.m_invMass * P2X;
        b2.m_linearVelocity.y += b2.m_invMass * P2Y;
        //b2.m_angularVelocity += b2.m_invI * b2Cross(r2, P2);
        b2.m_angularVelocity += b2.m_invI * (r2X * P2Y - r2Y * P2X);
    }
    SolveVelocityConstraints(step) {
        var b1 = this.m_body1;
        var b2 = this.m_body2;
        var tMat;
        //var r1 = b2Mul(b1.m_R, this.m_localAnchor1);
        tMat = b1.m_R;
        var r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
        var r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
        //var r2 = b2Mul(b2.m_R, this.m_localAnchor2);
        tMat = b2.m_R;
        var r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
        var r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
        // temp vars
        var v1X;
        var v1Y;
        var v2X;
        var v2Y;
        var P1X;
        var P1Y;
        var P2X;
        var P2Y;
        var Cdot;
        var impulse;
        var oldLimitImpulse;
        //{
        //b2Vec2 v1 = b1->m_linearVelocity + b2Cross(b1->m_angularVelocity, r1);
        v1X = b1.m_linearVelocity.x + (-b1.m_angularVelocity * r1Y);
        v1Y = b1.m_linearVelocity.y + (b1.m_angularVelocity * r1X);
        //b2Vec2 v2 = b2->m_linearVelocity + b2Cross(b2->m_angularVelocity, r2);
        v2X = b2.m_linearVelocity.x + (-b2.m_angularVelocity * r2Y);
        v2Y = b2.m_linearVelocity.y + (b2.m_angularVelocity * r2X);
        //Cdot = -b2Dot(this.m_u1, v1) - this.m_ratio * b2Dot(this.m_u2, v2);
        Cdot = -(this.m_u1.x * v1X + this.m_u1.y * v1Y) - this.m_ratio * (this.m_u2.x * v2X + this.m_u2.y * v2Y);
        impulse = -this.m_pulleyMass * Cdot;
        this.m_pulleyImpulse += impulse;
        //b2Vec2 P1 = -impulse * this.m_u1;
        P1X = -impulse * this.m_u1.x;
        P1Y = -impulse * this.m_u1.y;
        //b2Vec2 P2 = -this.m_ratio * impulse * this.m_u2;
        P2X = -this.m_ratio * impulse * this.m_u2.x;
        P2Y = -this.m_ratio * impulse * this.m_u2.y;
        //b1.m_linearVelocity += b1.m_invMass * P1;
        b1.m_linearVelocity.x += b1.m_invMass * P1X;
        b1.m_linearVelocity.y += b1.m_invMass * P1Y;
        //b1.m_angularVelocity += b1.m_invI * b2Cross(r1, P1);
        b1.m_angularVelocity += b1.m_invI * (r1X * P1Y - r1Y * P1X);
        //b2.m_linearVelocity += b2.m_invMass * P2;
        b2.m_linearVelocity.x += b2.m_invMass * P2X;
        b2.m_linearVelocity.y += b2.m_invMass * P2Y;
        //b2.m_angularVelocity += b2.m_invI * b2Cross(r2, P2);
        b2.m_angularVelocity += b2.m_invI * (r2X * P2Y - r2Y * P2X);
        //}
        if (this.m_limitState1 == b2Joint.e_atUpperLimit) {
            //b2Vec2 v1 = b1->m_linearVelocity + b2Cross(b1->m_angularVelocity, r1);
            v1X = b1.m_linearVelocity.x + (-b1.m_angularVelocity * r1Y);
            v1Y = b1.m_linearVelocity.y + (b1.m_angularVelocity * r1X);
            //float32 Cdot = -b2Dot(this.m_u1, v1);
            Cdot = -(this.m_u1.x * v1X + this.m_u1.y * v1Y);
            impulse = -this.m_limitMass1 * Cdot;
            oldLimitImpulse = this.m_limitImpulse1;
            this.m_limitImpulse1 = b2Math.b2Max(0.0, this.m_limitImpulse1 + impulse);
            impulse = this.m_limitImpulse1 - oldLimitImpulse;
            //b2Vec2 P1 = -impulse * this.m_u1;
            P1X = -impulse * this.m_u1.x;
            P1Y = -impulse * this.m_u1.y;
            //b1.m_linearVelocity += b1->m_invMass * P1;
            b1.m_linearVelocity.x += b1.m_invMass * P1X;
            b1.m_linearVelocity.y += b1.m_invMass * P1Y;
            //b1.m_angularVelocity += b1->m_invI * b2Cross(r1, P1);
            b1.m_angularVelocity += b1.m_invI * (r1X * P1Y - r1Y * P1X);
        }
        if (this.m_limitState2 == b2Joint.e_atUpperLimit) {
            //b2Vec2 v2 = b2->m_linearVelocity + b2Cross(b2->m_angularVelocity, r2);
            v2X = b2.m_linearVelocity.x + (-b2.m_angularVelocity * r2Y);
            v2Y = b2.m_linearVelocity.y + (b2.m_angularVelocity * r2X);
            //float32 Cdot = -b2Dot(this.m_u2, v2);
            Cdot = -(this.m_u2.x * v2X + this.m_u2.y * v2Y);
            impulse = -this.m_limitMass2 * Cdot;
            oldLimitImpulse = this.m_limitImpulse2;
            this.m_limitImpulse2 = b2Math.b2Max(0.0, this.m_limitImpulse2 + impulse);
            impulse = this.m_limitImpulse2 - oldLimitImpulse;
            //b2Vec2 P2 = -impulse * this.m_u2;
            P2X = -impulse * this.m_u2.x;
            P2Y = -impulse * this.m_u2.y;
            //b2->m_linearVelocity += b2->m_invMass * P2;
            b2.m_linearVelocity.x += b2.m_invMass * P2X;
            b2.m_linearVelocity.y += b2.m_invMass * P2Y;
            //b2->m_angularVelocity += b2->m_invI * b2Cross(r2, P2);
            b2.m_angularVelocity += b2.m_invI * (r2X * P2Y - r2Y * P2X);
        }
    }
    SolvePositionConstraints() {
        var b1 = this.m_body1;
        var b2 = this.m_body2;
        var tMat;
        //b2Vec2 s1 = this.m_ground->m_position + this.m_groundAnchor1;
        var s1X = this.m_ground.m_position.x + this.m_groundAnchor1.x;
        var s1Y = this.m_ground.m_position.y + this.m_groundAnchor1.y;
        //b2Vec2 s2 = this.m_ground->m_position + this.m_groundAnchor2;
        var s2X = this.m_ground.m_position.x + this.m_groundAnchor2.x;
        var s2Y = this.m_ground.m_position.y + this.m_groundAnchor2.y;
        // temp vars
        var r1X;
        var r1Y;
        var r2X;
        var r2Y;
        var p1X;
        var p1Y;
        var p2X;
        var p2Y;
        var length1;
        var length2;
        var C;
        var impulse;
        var oldLimitPositionImpulse;
        var linearError = 0.0;
        {
            //var r1 = b2Mul(b1.m_R, this.m_localAnchor1);
            tMat = b1.m_R;
            r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
            r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
            //var r2 = b2Mul(b2.m_R, this.m_localAnchor2);
            tMat = b2.m_R;
            r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
            r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
            //b2Vec2 p1 = b1->m_position + r1;
            p1X = b1.m_position.x + r1X;
            p1Y = b1.m_position.y + r1Y;
            //b2Vec2 p2 = b2->m_position + r2;
            p2X = b2.m_position.x + r2X;
            p2Y = b2.m_position.y + r2Y;
            // Get the pulley axes.
            //this.m_u1 = p1 - s1;
            this.m_u1.Set(p1X - s1X, p1Y - s1Y);
            //this.m_u2 = p2 - s2;
            this.m_u2.Set(p2X - s2X, p2Y - s2Y);
            length1 = this.m_u1.Length();
            length2 = this.m_u2.Length();
            if (length1 > b2Settings.b2_linearSlop) {
                //this.m_u1 *= 1.0f / length1;
                this.m_u1.Multiply(1.0 / length1);
            }
            else {
                this.m_u1.SetZero();
            }
            if (length2 > b2Settings.b2_linearSlop) {
                //this.m_u2 *= 1.0f / length2;
                this.m_u2.Multiply(1.0 / length2);
            }
            else {
                this.m_u2.SetZero();
            }
            C = this.m_constant - length1 - this.m_ratio * length2;
            linearError = b2Math.b2Max(linearError, Math.abs(C));
            C = b2Math.b2Clamp(C, -b2Settings.b2_maxLinearCorrection, b2Settings.b2_maxLinearCorrection);
            impulse = -this.m_pulleyMass * C;
            p1X = -impulse * this.m_u1.x;
            p1Y = -impulse * this.m_u1.y;
            p2X = -this.m_ratio * impulse * this.m_u2.x;
            p2Y = -this.m_ratio * impulse * this.m_u2.y;
            b1.m_position.x += b1.m_invMass * p1X;
            b1.m_position.y += b1.m_invMass * p1Y;
            b1.m_rotation += b1.m_invI * (r1X * p1Y - r1Y * p1X);
            b2.m_position.x += b2.m_invMass * p2X;
            b2.m_position.y += b2.m_invMass * p2Y;
            b2.m_rotation += b2.m_invI * (r2X * p2Y - r2Y * p2X);
            b1.m_R.Set(b1.m_rotation);
            b2.m_R.Set(b2.m_rotation);
        }
        if (this.m_limitState1 == b2Joint.e_atUpperLimit) {
            //b2Vec2 r1 = b2Mul(b1->m_R, this.m_localAnchor1);
            tMat = b1.m_R;
            r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
            r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
            //b2Vec2 p1 = b1->m_position + r1;
            p1X = b1.m_position.x + r1X;
            p1Y = b1.m_position.y + r1Y;
            //this.m_u1 = p1 - s1;
            this.m_u1.Set(p1X - s1X, p1Y - s1Y);
            length1 = this.m_u1.Length();
            if (length1 > b2Settings.b2_linearSlop) {
                //this.m_u1 *= 1.0 / length1;
                this.m_u1.x *= 1.0 / length1;
                this.m_u1.y *= 1.0 / length1;
            }
            else {
                this.m_u1.SetZero();
            }
            C = this.m_maxLength1 - length1;
            linearError = b2Math.b2Max(linearError, -C);
            C = b2Math.b2Clamp(C + b2Settings.b2_linearSlop, -b2Settings.b2_maxLinearCorrection, 0.0);
            impulse = -this.m_limitMass1 * C;
            oldLimitPositionImpulse = this.m_limitPositionImpulse1;
            this.m_limitPositionImpulse1 = b2Math.b2Max(0.0, this.m_limitPositionImpulse1 + impulse);
            impulse = this.m_limitPositionImpulse1 - oldLimitPositionImpulse;
            //P1 = -impulse * this.m_u1;
            p1X = -impulse * this.m_u1.x;
            p1Y = -impulse * this.m_u1.y;
            b1.m_position.x += b1.m_invMass * p1X;
            b1.m_position.y += b1.m_invMass * p1Y;
            //b1.m_rotation += b1.m_invI * b2Cross(r1, P1);
            b1.m_rotation += b1.m_invI * (r1X * p1Y - r1Y * p1X);
            b1.m_R.Set(b1.m_rotation);
        }
        if (this.m_limitState2 == b2Joint.e_atUpperLimit) {
            //b2Vec2 r2 = b2Mul(b2->m_R, this.m_localAnchor2);
            tMat = b2.m_R;
            r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
            r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
            //b2Vec2 p2 = b2->m_position + r2;
            p2X = b2.m_position.x + r2X;
            p2Y = b2.m_position.y + r2Y;
            //this.m_u2 = p2 - s2;
            this.m_u2.Set(p2X - s2X, p2Y - s2Y);
            length2 = this.m_u2.Length();
            if (length2 > b2Settings.b2_linearSlop) {
                //this.m_u2 *= 1.0 / length2;
                this.m_u2.x *= 1.0 / length2;
                this.m_u2.y *= 1.0 / length2;
            }
            else {
                this.m_u2.SetZero();
            }
            C = this.m_maxLength2 - length2;
            linearError = b2Math.b2Max(linearError, -C);
            C = b2Math.b2Clamp(C + b2Settings.b2_linearSlop, -b2Settings.b2_maxLinearCorrection, 0.0);
            impulse = -this.m_limitMass2 * C;
            oldLimitPositionImpulse = this.m_limitPositionImpulse2;
            this.m_limitPositionImpulse2 = b2Math.b2Max(0.0, this.m_limitPositionImpulse2 + impulse);
            impulse = this.m_limitPositionImpulse2 - oldLimitPositionImpulse;
            //P2 = -impulse * this.m_u2;
            p2X = -impulse * this.m_u2.x;
            p2Y = -impulse * this.m_u2.y;
            //b2.m_position += b2.m_invMass * P2;
            b2.m_position.x += b2.m_invMass * p2X;
            b2.m_position.y += b2.m_invMass * p2Y;
            //b2.m_rotation += b2.m_invI * b2Cross(r2, P2);
            b2.m_rotation += b2.m_invI * (r2X * p2Y - r2Y * p2X);
            b2.m_R.Set(b2.m_rotation);
        }
        return linearError < b2Settings.b2_linearSlop;
    }
}
// static
b2PulleyJoint.b2_minPulleyLength = b2Settings.b2_lengthUnitsPerMeter;
b2Joint.Register(b2Joint.e_pulleyJoint, b2PulleyJoint.Create);
